A supercapacitor (SC), sometime referred to as an ultra-capacitor, and formerly referred to as an electric double-layer capacitor (EDLC), is a high-capacity, electrochemical capacitor with capacitance values much higher than other capacitors, but lower voltage limits. A supercapacitor bridges the gap between electrolytic capacitors and rechargeable batteries. They typically store 10 to 100 times more energy per unit volume or mass than electrolytic capacitors, and accept and deliver charge much faster than batteries, and can tolerate more charge and discharge cycles than chargeable batteries.
Supercapacitors may be used in applications requiring rapid charge and discharge cycles, rather than long-term compact energy storage. Typically, supercapacitors use electrostatic double-layer capacitance or electrochemical pseudo-capacitance, or a combination of both. Supercapacitors are typically low-voltage components, which typically exhibit much longer lifetime than batteries. Supercapacitors generally have advantage in applications where a large amount of power is required for a relatively short time, or where a very high number of charge/discharge cycles is anticipated, or a longer lifetime is needed.
The ability to provide enhanced supercapacitor operation remains an area of interest and continued research for, for instance, establishing commercial advantage in the industry.